This mistake causes two possible bugs. I believe they are both
harmless IRL.
BUG 1: memory stomping
When we call the memset, we are overwriting two 0 bytes past the end
of packed_cell_t.body. But I think that's harmless in practice,
because the definition of packed_cell_t is:
// ...
typedef struct packed_cell_t {
TOR_SIMPLEQ_ENTRY(packed_cell_t) next;
char body[CELL_MAX_NETWORK_SIZE];
uint32_t inserted_time;
} packed_cell_t;
So we will overwrite either two bytes of inserted_time, or two bytes
of padding, depending on how the platform handles alignment.
If we're overwriting padding, that's safe.
If we are overwriting the inserted_time field, that's also safe: In
every case where we call cell_pack() from connection_or.c, we ignore
the inserted_time field. When we call cell_pack() from relay.c, we
don't set or use inserted_time until right after we have called
cell_pack(). SO I believe we're safe in that case too.
BUG 2: memory exposure
The original reason for this memset was to avoid the possibility of
accidentally leaking uninitialized ram to the network. Now
remember, if wide_circ_ids is false on a connection, we shouldn't
actually be sending more than 512 bytes of packed_cell_t.body, so
these two bytes can only leak to the network if there is another bug
somewhere else in the code that sends more data than is correct.
Fortunately, in relay.c, where we allocate packed_cell_t in
packed_cell_new() , we allocate it with tor_malloc_zero(), which
clears the RAM, right before we call cell_pack. So those
packed_cell_t.body bytes can't leak any information.
That leaves the two calls to cell_pack() in connection_or.c, which
use stack-alocated packed_cell_t instances.
In or_handshake_state_record_cell(), we pass the cell's contents to
crypto_digest_add_bytes(). When we do so, we get the number of
bytes to pass using the same setting of wide_circ_ids as we passed
to cell_pack(). So I believe that's safe.
In connection_or_write_cell_to_buf(), we also use the same setting
of wide_circ_ids in both calls. So I believe that's safe too.
I introduced this bug with 1c0e87f6d8
back in 0.2.4.11-alpha; it is bug 22737 and CID 1401591
On an hidden service rendezvous circuit, a BEGIN_DIR could be sent
(maliciously) which would trigger a tor_assert() because
connection_edge_process_relay_cell() thought that the circuit is an
or_circuit_t but is an origin circuit in reality.
Fixes#22494
Reported-by: Roger Dingledine <arma@torproject.org>
Signed-off-by: David Goulet <dgoulet@torproject.org>
When directory authorities reject a router descriptor due to keypinning,
free the router descriptor rather than leaking the memory.
Fixes bug 22370; bugfix on 0.2.7.2-alpha.
Directory authorities now reject relays running versions
0.2.9.1-alpha through 0.2.9.4-alpha, because those relays
suffer from bug 20499 and don't keep their consensus cache
up-to-date.
Resolves ticket 20509.
Replace the 177 fallbacks originally introduced in Tor 0.2.9.8 in
December 2016 (of which ~126 were still functional), with a list of
151 fallbacks (32 new, 119 existing, 58 removed) generated in May 2017.
Resolves ticket 21564.
Closes bug 22245; bugfix on 0.0.9rc1, when bandwidth accounting was
first introduced.
Found by Andrey Karpov and reported at https://www.viva64.com/en/b/0507/
One (HeapEnableTerminationOnCorruption) is on-by-default since win8;
the other (PROCESS_DEP_DISABLE_ATL_THUNK_EMULATION) supposedly only
affects ATL, which (we think) we don't use. Still, these are good
hygiene. Closes ticket 21953.
The GETINFO extra-info/digest/<digest> broke in commit 568dc27a19 that
refactored the base16_decode() API to return the decoded length.
Unfortunately, that if() condition should have checked for the correct length
instead of an error which broke the command in tor-0.2.9.1-alpha.
Fixes#22034
Signed-off-by: David Goulet <dgoulet@torproject.org>
This change is the only one necessary to allow future versions of
the microdescriptor consensus to replace every 'published' date with
e.g. 2038-01-01 00:00:00; this will save 50-75% in compressed
microdescriptor diff size, which is quite significant.
This commit is a minimal change for 0.2.9; future series will
reduce the use of the 'published' date even more.
Implements part of ticket 21642; implements part of proposal 275.
strto* and _atoi64 accept +, -, and various whitespace before numeric
characters. And permitted whitespace is different between POSIX and Windows.
Fixes bug 21507 and part of 21508; bugfix on 0.0.8pre1.
Fix for TROVE-2017-001 and bug 21278.
(Note: Instead of handling signed ints "correctly", we keep the old
behavior, except for the part where we would crash with -ftrapv.)
This reverts commit 5446cb8d3d.
The underlying revert was done in 0.2.6, since we aren't backporting
seccomp2 loosening fixes to 0.2.6. But the fix (for 17354) already
went out in 0.2.7.4-rc, so we shouldn't revert it in 0.2.7.
maint-0.2.7-redux is an attempt to try to re-create a plausible
maint-0.2.7 branch. I've started from the tor-0.2.7.6, and then I
merged maint-0.2.6 into the branch.
This has produced 2 conflicts: one related to the
rendcommon->rendcache move, and one to the authority refactoring.
Check size argument to memwipe() for underflow.
Closes bug #18089. Reported by "gk", patch by "teor".
Bugfix on 0.2.3.25 and 0.2.4.6-alpha (#7352),
commit 49dd5ef3 on 7 Nov 2012.
The length of auth_data from an INTRODUCE2 cell is checked when the
auth_type is recognized (1 or 2), but not for any other non-zero
auth_type. Later, auth_data is assumed to have at least
REND_DESC_COOKIE_LEN bytes, leading to a client-triggered out of bounds
read.
Fixed by checking auth_len before comparing the descriptor cookie
against known clients.
Fixes#15823; bugfix on 0.2.1.6-alpha.
Determining if OpenSSL structures are opaque now uses an autoconf check
instead of comparing the version number. Some definitions have been
moved to their own check as assumptions which were true for OpenSSL
with opaque structures did not hold for LibreSSL. Closes ticket 21359.
When marking for close a circuit, the reason value, a integer, was assigned to
a uint16_t converting any negative reasons (internal) to the wrong value. On
the HS side, this was causing the client to flag introduction points to be
unreachable as the internal reason was wrongfully converted to a positive
16bit value leading to flag 2 out of 3 intro points to be unreachable.
Fixes#20307 and partially fixes#21056
Signed-off-by: David Goulet <dgoulet@torproject.org>
The server-side clipping now clamps to one of two values, both
for what to report, and how long to cache.
Additionally, we move some defines to dns.h, and give them better
names.
This helps protect against bugs where any part of a buf_t's memory
is passed to a function that expects a NUL-terminated input.
It also closes TROVE-2016-10-001 (aka bug 20384).
Replace the 81 remaining fallbacks of the 100 originally introduced
in Tor 0.2.8.3-alpha in March 2016, with a list of 177 fallbacks
(123 new, 54 existing, 27 removed) generated in December 2016.
Resolves ticket 20170.
In get_token(), we could read one byte past the end of the
region. This is only a big problem in the case where the region
itself is (a) potentially hostile, and (b) not explicitly
nul-terminated.
This patch fixes the underlying bug, and also makes sure that the
one remaining case of not-NUL-terminated potentially hostile data
gets NUL-terminated.
Fix for bug 21018, TROVE-2016-12-002, and CVE-2016-1254
The signed_descriptor_move() was not releasing memory inside the destination
object before overwriting it with the source object. This commit adds a reset
function that free that memory inside a signed descriptor object and zero it.
Closes#20715.
Signed-off-by: David Goulet <dgoulet@torproject.org>
Tor 0.2.9 has a broader range of fixes and workarounds here, but for
0.2.8, we're just going to maintain the existing behavior.
(The alternative would be to backport both
1eba088054 and
16fcbd21c9 , but the latter is kind of
a subtle kludge in the configure.ac script, and I'm not a fan of
backporting that kind of thing.)
(OpenSSL 1.1 makes EVP_CIPHER_CTX opaque, _and_ adds acceleration
for counter mode on more architectures. So it won't work if we try
the older approach, and it might help if we try the newer one.)
Fixes bug 20588.
When computing old Tor protocol line version in protover, we were looking at
0.2.7.5 twice instead of the specific case for 0.2.9.1-alpha.
Fixes#20810
Signed-off-by: David Goulet <dgoulet@torproject.org>
newconn->address is strdup'ed twice when new_type == CONN_TYPE_AP
and conn->socket_family == AF_UNIX. Whilst here, juggle code to
make sure newconn->port is assigned from an initialised value in
the above case.
Instead, refuse to start tor if any hidden service key has been used in
a different hidden service anonymity mode.
Fixes bug 20638; bugfix on 17178 in 0.2.9.3-alpha; reported by ahf.
The original single onion service poisoning code checked poisoning state
in options_validate, and poisoned in options_act. This was problematic,
because the global array of hidden services had not been populated in
options_validate (and there were ordrering issues with hidden service
directory creation).
This patch fixes this issue in rend_service_check_dir_and_add, which:
* creates the directory, or checks permissions on an existing directory, then
* checks the poisoning state of the directory, then
* poisons the directory.
When validating, only the permissions checks and the poisoning state checks
are perfomed (the directory is not modified).
Apple is supposed to decorate their function declarations with
macros to indicate which OSX version introduced them, so that you
can tell the compiler that you want to build against certain
versions of OSX. But they forgot to do that for clock_gettime() and
getentropy(), both of which they introduced in 10.12.
This patch adds a kludge to the configure.ac script where, if we
detect that we are targeting OSX 10.11 or earlier, we don't even probe
to see if the two offending functions are present.
Closes ticket 20235.
For relays that don't know their own address, avoid attempting
a local hostname resolve for each descriptor we download. Also cut
down on the number of "Success: chose address 'x.x.x.x'" log lines.
Fixes bugs 20423 and 20610; bugfix on 0.2.8.1-alpha.
Single onion services and Tor2web deliberately create long-term one-hop
circuits to their intro and rend points, respectively.
These log messages are intended to diagnose issue 8387, which relates to
circuits hanging around forever for no reason.
Fixes bug 20613; bugfix on 0.2.9.1-alpha. Reported by "pastly".
It's not okay to use the same varargs list twice, and apparently
some windows build environments produce code here that would leave
tor_asprintf() broken. Fix for bug 20560; bugfix on 0.2.2.11-alpha
when tor_asprintf() was introduced.
Because as Teor puts it: "[Resetting on 503] is exactly what we
don't want when relays are busy - imagine clients doing an automatic
reset every time they DoS a relay..."
Fixes bug 20593.
It's only safe to remove the failure limit (per 20536) if we are in
fact waiting a bit longer each time we try to download.
Fixes bug 20534; bugfix on 0.2.9.1-alpha.
If a consensus expires while we are waiting for certificates to download,
stop waiting for certificates.
If we stop waiting for certificates less than a minute after we started
downloading them, do not consider the certificate download failure a
separate failure.
Fixes bug 20533; bugfix on commit e0204f21 in 0.2.0.9-alpha.
Relays do not deliberately launch multiple attempts, so the impact of this
bug should be minimal. This fix also defends against bugs like #20499.
Bugfix on 0.2.8.1-alpha.
(OpenSSL 1.1 makes EVP_CIPHER_CTX opaque, _and_ adds acceleration
for counter mode on more architectures. So it won't work if we try
the older approach, and it might help if we try the newer one.)
Fixes bug 20588.
In our code to write public keys to a string, for some unfathomable
reason since 253f0f160e, we would allocate a memory BIO, then
set the NOCLOSE flag on it, extract its memory buffer, and free it.
Then a little while later we'd free the memory buffer with
BUF_MEM_free().
As of openssl 1.1 this doesn't work any more, since there is now a
BIO_BUF_MEM structure that wraps the BUF_MEM structure. This
BIO_BUF_MEM doesn't get freed in our code.
So, we had a memory leak!
Is this an openssl bug? Maybe. But our code was already pretty
silly. Why mess around with the NOCLOSE flag here when we can just
keep the BIO object around until we don't need the buffer any more?
Fixes bug 20553; bugfix on 0.0.2pre8
